Esophageal Dysmotility in Young Dogs

Background:Abnormal esophageal motility can exist without megaesophagus, although its prevalence in dogs is unknown and its cause has not been elucidated. Hypothesis:Esophageal dysmotility without overt megaesophagus exists in both symptomatic and asymptomatic young dogs, and motility can improve with age. Animals:Dogs examined at the Department of Veterinary Medicine, University of Cambridge for regurgitation, but without evidence of megaesophagus on radiographs, and a further group of asymptomatic dogs. Methods:Dogs underwent an initial and a repeat videofluoroscopic swallowing study. Images were reviewed and 5 criteria of esophageal motility evaluated. Results:Eight affected dogs were identified (median age 9 months), and terrier dogs predominated (6 terriers of 3 breeds). Esophageal motility was reduced either globally (n = 3) or segmentally (n = 5). Repeat examination at a median of 3 months revealed that regurgitation had reduced or resolved in the majority of terrier dogs, and 4 of 6 cases demonstrated an improvement in esophageal motility. Videofluoroscopic evaluation of young (median age 11 months) asymptomatic dogs of various breeds (n = 22) revealed evidence of esophageal dysmotility in 4 of 5 control terrier dogs. Repeat evaluation demonstrated an improvement in esophageal motility in 3 dogs. Conclusion and Clinical Importance: Esophageal dysmotility without overt megaesophagus occurs in young terrier dogs, and affected animals can be symptomatic or asymptomatic. Further, an improvement in esophageal motility occurs with time in some dogs, and might represent a syndrome of delayed esophageal maturation.